Letter: Slugs without pain

Sir: Mr Hayward may regard using nematode worms to eat slugs as 'immoral' (letter, 4 March), but the possibility of a slug, let alone any less advanced invertebrate, suffering an 'agonising death' is unlikely, as its nervous system is too primitive for it to feel pain. An analogy would be for a human to have its coat gradually snipped away at; something to avoid, but not at all painful.